PIP: The dietary, behavioral and in vitro methods of sex selection are evaluated for physicians to advise patients who desire to plan the gender of their families, but for whom chorionic villus sampling and elective abortion is unacceptable. A diet based on high potassium and sodium, and low magnesium and calcium for couples desiring boys claimed 84% success. No controls were provided. The in vivo methods typically involve timing of intercourse in relation to ovulation, sometimes combined with alkaline douche, female orgasm before male, rear-entry, for boys, and other variations for girls. Reports of behavioral methods have been inconsistent, especially when artificial insemination results are included for comparison, nor do sperm counts back up these claims. The in vitro techniques include a patented albumin density gradient method, franchised by Gametrics Ltd., and several others. No controlled trials have been published on these methods. Some of the in vitro methods are expensive, or may dilute sperm so much that several attempts will be necessary. Patients should be advised of the uncertainty of these claims, but perhaps told that dietary methods, if used for only 1.5 cycles may not be harmful.